mp_units::value_cast

Synopsis

Declared in <mp-units/framework/value_cast.h>

template<
    typename ToRep,
    typename FwdQP,
    RoundingPolicy Policy = truncated_t,
    QuantityPoint QP = std::remove_cvref_t<FwdQP>>
requires RepresentationOf<ToRep, QP::quantity_spec> && std::constructible_from<ToRep, typename QP::rep> &&
           detail::ValidRoundingPolicyFor<Policy, typename QP::rep, ToRep>
[[nodiscard]]
constexpr
quantity_point<QP::reference, QP::point_origin, ToRep>
value_cast(
    FwdQP&& qp,
    Policy policy = Policy{});

Description

Implicit conversions between quantity points of different types are allowed only for "safe" (e.g. non-truncating) conversion. In truncating cases an explicit cast have to be used.

auto qp = value_cast<int>(quantity_point{1.23 * ms});

Return Value

A quantity point

NOTE

The return value should not be discarded.

Template Parameters

Name	Description
ToRep	a representation type to use for a target quantity point

Parameters

Name	Description
policy	an optional rounding policy (`truncated` when not provided)